Zits are a familiar foe, plugging the pores of people young and old, all around the world.

Acne is the most common skin disorder in the United States. An estimated 80 percent of all people between the ages of 11 and 30 have outbreaks, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases. Even 50-year-olds endure flare-ups.

Eliminating problem skin isn't easy. Dermatologists, mothers and even P. Diddy have worked to rid us of blemishes.

Producing Pimples


A pilosebaceous units (PSU) consists of a sebaceous gland connected to a canal, called a follicle, that contains a fine hair that emerges from a pore. The glands make an oily sebum that normally empties onto the skin through the pore. Cells called keratinocytes line the follicle. The setup can get plugged, preventing sebum from escaping. Bacteria that's normally on the skin festers in the oily mix, producing chemicals and enzymes and attracting white blood cells that cause inflammation. And you know what happens next.


SOURCE: NIH

Yet while research on acne remedies is extensive and treatments fill drugstore aisles, myths about the condition are hard to wash away.

Mud mask

Contrary to what your mother told you, cleaning your face isn't the cure-all to clean-looking skin. Dirt doesn't breed zits.

The nasty buggers form when your tiny hair follicles get clogged, blocking the normal exit pathway for oil, called sebum, to escape to the surface of the skin.

Although scientists have yet to pinpoint the cause of acne, androgen hormones—which rise during puberty in boys and girls and continue to fluctuate during a woman's menstrual cycle—cause the sebaceous glands to produce more sebum. Cosmetics, drugs such as lithium, and genetics also contribute to an individual's zit potential.

Back under the skin, things get uglier when the oil mixes with cells lining the follicle, making a comfortable environment for bacteria to move in and cause inflammation. Enough swelling will break down the follicle walls, and the plugged-up mess will unload into the skin. That's when pimples rear their ugly heads.

Filthy-looking blackheads feed the misconception that acne grows on grime. In reality, sebum turns the color of mud when exposed to air.

Scrubbing away at spotty skin too much or too often can actually worsen the skin condition.

"The concept that you can wash away your acne is not based on true fact," said dermatologist Alexa Boer Kimball, director of Harvard University's Clinical Unit for Research Trials in Skin.

She conducted a survey to test the hygiene hypothesis, asking college men to cleanse their faces either once, twice, or four times a day for six weeks. The washing results showed no difference between the regimens. Cleaning twice a day is probably best, says Kimball. 

Chocolate and fries

Fables about acne have traveled beyond the bathroom and into the kitchen. Chocolate candy bars and greasy foods have long been accused of tarnishing complexions, and drinking water has been deemed the ultimate therapy.

A number of studies in the 1960's and 70's set out to debunk the idea that what you eat pops up on your face. Today dermatologists agree that the experiments were not conducted well.

Recently, research has shown that drinking milk may modestly increase the risk of acne. However, the story on diet is still evolving.

"The role of diet is not yet clear," Kendall told LiveScience. "The overall effect of diet on acne is not real big, but it's something we need to study more. But we're not talking about too much chocolate or too many fries."

As for the holy grail of drinking lots of water to ward off bad bumps, Kendall says it's completely unfounded.

Treatments

Dermatologists have an arsenal of treatments that can help.

Ingredients in over-the-counter soaps and lotions can do the trick for some skin. Benzoyl peroxide kills off bacteria, while salycic acid and sulphur break down whiteheads and blackheads.

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For more severe cases, doctors may prescribe antibiotics to curb bacterial growth or large doses of vitamin A derivatives, such as Accutane, which unplug zits and can help prevent scarring.

"We have a lot of good treatments," Kimball said. "The key is coming up with a regimen you like to use and will use consistently."

Pimple products in the pipeline combine several medicines to make regimens easier on the patient. For instance, rather than remembering to use two or more products twice a day, a patient may only need to use one medicine, once a day.

One last piece of advice: Do listen to your mother when she tells you to keep your hands off your face.

"Picking is not a good idea," Kimball said. "Almost always, you're making it worse."